HR: 0800h
AN: H41B-0295    [Abstracts]
TI: Prediction of Mass Wasting, Erosion, and Sediment Transport With the Distributed Hydrology-Soil-Vegetation Model
AU: Doten, C O
EM: colleen@hydro.washington.edu
AF: Department of Civil and Environmental Engineering, University of Washington, Seattle, WA 98195
AU: * Lanini, J S
EM: jlanini@hydro.washington.edu
AF: Department of Civil and Environmental Engineering, University of Washington, Seattle, WA 98195
AU: Bowling, L C
EM: bowling@purdue.edu
AF: Purdue University, Department of Agronomy, Lilly Hall of Life Sciences, 915 West State Street, West Lafayette, IN 47907
AU: Lettenmaier, D P
EM: dennisl@u.washington.edu
AF: Department of Civil and Environmental Engineering, University of Washington, Seattle, WA 98195
AB: Erosion and sediment transport in a temperate forested watershed are predicted with a new sediment module linked to the Distributed Hydrology-Soil-Vegetation Model (DHSVM). The DHSVM sediment module represents the main sources of sediment generation in forested environments: mass wasting, hillslope erosion and road surface erosion. It produces failures based on a factor-of-safety analysis with the infinite slope model through use of stochastically generated soil and vegetation parameters. Failed material is routed downslope with a rule-based scheme that determines sediment delivery to streams. Sediment from hillslopes and road surfaces is also transported to the channel network. Basin sediment yield is predicted with a simple channel sediment routing scheme. The model was applied to the Rainy Creek catchment, a tributary of the Wenatchee River which drains the east slopes of the Cascade Mountains, and Hard and Ware Creeks on the west slopes of the Cascades. In these initial applications, the model produced plausible sediment yield and ratios of landsliding and surface erosion , when compared to published rates for similar catchments in the Pacific Northwest. We have also used the model to examine the implications of fires and logging road removal on sediment generation in the Rainy Creek catchment. Generally, in absolute value, the predicted changes (increased sediment generation) following fires, which are primarily associated with increased slope failures, are much larger than the modest changes (reductions in sediment yield) associated with road obliteration, although the small sensitivity to forest road obliteration may be due in part to the relatively low road density in the Rainy Creek catchment, and to mechanisms, such as culvert failure, that are not represented in the model.
DE: 1803 Anthropogenic effects
DE: 1815 Erosion and sedimentation
DE: 1860 Runoff and streamflow
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting